Evidence map›Paper›PMID 41995888›Full record

ArticleVeterinary research communications2026

Molecular epidemiology of ESBL-producing Escherichia coli causing clinical and subclinical bovine mastitis: associations between multidrug resistance, virulence genes, and phylogroups.

Elif Çokan Madenci, Farouk Hassan, Mehmet Kenan Türkyılmaz, Süheyla Türkyılmaz

Abstract read
In one paragraph

Article in Veterinary research communications, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

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0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

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3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

4 authors.

Elif Çokan MadenciInstitute of Health Sciences, Aydın Adnan Menderes University, Aydın, Türkiye.ORCID http://orcid.org/0009-0000-3891-6960
Farouk HassanInstitute of Health Sciences, Aydın Adnan Menderes University, Aydın, Türkiye.ORCID http://orcid.org/0000-0002-6588-3866
Mehmet Kenan TürkyılmazDepartment of Animal Science, Faculty of Veterinary Medicine, Aydın Adnan Menderes University, Aydın, Türkiye.ORCID http://orcid.org/0000-0002-7600-2390
Süheyla TürkyılmazDepartment of Microbiology, Faculty of Veterinary Medicine, Aydın Adnan Menderes University, Aydın, Türkiye. sturkyilmaz@adu.edu.tr.ORCID http://orcid.org/0000-0002-1363-4534

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli are increasingly implicated in bovine mastitis and may serve as a reservoir of antimicrobial resistance with public health relevance. This study aimed to characterize the antimicrobial resistance, ESBL gene distribution, virulence-associated genes, integron carriage, and phylogenetic backgrounds of ESBL-producing E.coli isolated from bovine mastitis, and to compare these features between clinical and subclinical cases. A total of 400 bovine mastitis milk samples collected between June 2024 and May 2025 were screened for ESBL-producing bacteria, followed by phenotypic confirmation and antimicrobial susceptibility testing. Molecular characterization targeted the major ESBL genes, bla CTX−M, blaTEM, and bla SHV, class 1 and 2 integrons (intI1, intI2), 12 virulence-associated genes, and phylogenetic backgrounds determined by the Clermont method. Among 300 Gram-negative isolates, 135/300 (45.0%) E.coli isolates were confirmed as ESBL producers. Multidrug resistance was detected in 94/95 (98.9%) clinical isolates compared with 15/40 (37.5%) subclinical isolates, and clinical isolates showed significantly higher resistance to fluoroquinolones and aztreonam. Although bla CTX−M predominated overall [90/95 (94.7%) in clinical mastitis and 30/40 (75.0%) in subclinical mastitis], bla TEM and bla SHV were also more frequent among clinical isolates [65/95 (68.4%) and 55/95 (57.9%), respectively] than among subclinical isolates [15/40 (37.5%) for both]. Class 1 integrons were common in both groups and did not differ significantly by disease presentation, whereas dual intI1/intI2 carriage was more frequent among clinical isolates. Clinical isolates showed exclusive detection of colV [20/95 (21.1%) vs. 0/40], whereas subclinical isolates more frequently carried iroN [25/40 (62.5%) vs. 40/95 (42.1%)] and hlyF [30/40 (75.0%) vs. 50/95 (52.6%)]. Phylogroup B2 was more frequent among clinical isolates [45/95 (47.4%) vs. 10/40 (25.0%)], whereas phylogroup F was detected only among subclinical isolates [10/40 (25.0%) vs. 0/95]. In conclusion, ESBL-producing E.coli from clinical and subclinical bovine mastitis showed distinct molecular and phenotypic distributions, with clinical isolates more commonly associated with multidrug resistance, broader ESBL gene carriage, exclusive colV detection, and high-risk phylogenetic backgrounds. These findings support the value of integrated molecular surveillance to inform antimicrobial stewardship and One Health-oriented risk assessment in dairy production systems.

Indexed as

beta-LactamasesDrug Resistance, Multiple, BacterialEscherichia coliEscherichia coli InfectionsMastitis, BovineAnimalsAnti-Bacterial AgentsCattleFemaleIntegronsMicrobial Sensitivity TestsMolecular EpidemiologyPhylogenyVirulenceVirulence FactorsAnti-Bacterial Agentsbeta-LactamasesVirulence FactorsBovine mastitisEscherichia coliExtended-spectrum beta-lactamaseMultidrug resistanceOne healthVirulence factors

Identifiers

PMID41995888
PMCPMC13090260

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.